It was a vicious story of sexual assault followed by a bizarre murder-suicide that overwhelmed a Korean community both in Toronto and overseas.

As local media grabbed hold of a story already circulating on social media at hyper speed — quickly becoming a sensation among the sizeable Korean community in Canada — the news spread to South Korea almost overnight, dominating coverage by broadcasters and leading daily newspapers.

Trouble is, none of it was true.

In an Internet age of immediacy, where it can take less than an hour for a story or video to go viral, it took five days for the false reports to unravel, while English publications and local police remained mostly unaware of the story’s global spread.

The story began with Facebook posts from a man identified on his profile page as a 22-year-old University of Toronto student claiming to be the friend of a 19-year-old female Korean student who was sexually assaulted in the Yonge and Finch area by three Korean men in a G-class Mercedes SUV.

On Jan. 9, he posted in both Korean and English that the three men were dead following a murder-suicide in London, Ont., where the car was recovered.

The original post, which named the three men and their ages, had been shared by more than 140 people on Thursday when viewed by a Star reporter.

“Thank you all and share this message so that it is known throughout the community that these guys are now caught and got what they deserved,” the post concluded.

When Toronto’s Korea Times reporter Jay Jung twigged to the story, he said the original posts were already causing a sensation online.

“It went viral on the Internet, so we went for the source of the story,” he told the Star on Friday.

After Jung interviewed the man on Jan. 8, the story ran on the front page of the Times — the first Korean-language paper to report the story — though it indicated that police could not confirm the reports, he said.

On Friday, stories of the assault were still posted on the websites of Radio Korea, Seoul Broadcasting System, and several major newspapers in South Korea, including the Dong-A Ilbo.

But a second Times article by Jung the same day cast doubts on the original story, reiterating that police in Toronto and London were not confirming any of the reports.

Jung said he’s since spoken again with the Facebook poster about the story.

“He confessed himself yesterday, last night,” Jung said. “It turns out it’s all fabricated by him.”

The poster did not respond to a request for comment from The Star. His Facebook page has since been taken down.

When contacted by the Star on Thursday, police in Toronto and London said they had no knowledge of the alleged incidents.

Toronto Police spokesperson Mark Pugash said Friday there is concern that misinformation has been so widely disseminated within Toronto’s Korean community, which includes 34,220 people, according to the most recent census data — more than half of all Koreans living in Ontario.

“What concerns me is the damage this can cause to peoples’ sense of safety in Toronto,” he said. “If they believe that something that serious has happened, that can certainly have an effect on their perception of safety in the city and the way in which they behave in the city.”

Myong Yong Om, consul at the Consulate General of the Republic of Korea in Toronto, said any concern has been mitigated by a Ministry of Foreign Affairs press release from his government to local media sent Thursday, calling the reports false, and a notice posted to the consulate website Friday.

Meanwhile, Jung said, the story is now riding a second wave as news spreads about its lack of authenticity.

“It went viral again in Korea and here within (the) Korean community,” he said.

Greg Elmer, professor of media at Ryerson University, said the nature of the story — involving sexual assault — could have given it particular traction in the current media climate, given the recent headlines about sexual assault in India and prior assault cases here involving international students.

“Usually the accusation, which is always very dramatic, gets seen by a lot of eyeballs,” Elmer said, “the same not being true for the modification, the correction or the outright rejection of those stories.”